save_file.php代码

<?php
session_start();
$handle = fopen($_POST['original_file_name'], "w");
$text  = $_POST['file_contents'];
if(fwrite($handle, $text) == FALSE){
    $_SESSION['error'] = '<span class="redtxt">There was an error</span>';
}else{
    $_SESSION['error'] = '<span class="redtxt">File edited successfully</span>';
}
fclose($handle);
header("Location: ".$_POST['page']);
?>
read_file.php
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
    <title>Untitled Document</title>
</head>
<form action="savecontents.php" method="post">
<textarea name="file_contents" style="width:700px;height:600px;">
<?php
$fileName = "location/of/orignal/file/my_file.php";
$handle = fopen($fileName, "r");
while (!feof($handle)){
    $text = fgets($handle);
    echo $text;
}
?>
</textarea>
    <input type="hidden" value=" <? echo $fileName; ?> " name="original_file_name" />
</form>
<body>
</body>
</html>